Footwear and process of making the same



Aug. 9, 1932. H. D. RICE FOOTWEAR AND PROCESS OF MAKING THE SAME v Filed April 15. 1931 HNVENTOR www@ A765 BY Q ATTORNEY atentcd ng.. @9 il32 UNITED STATES PORATION OF CONNECTICUT FOOTWEAR AND PROCESS Ol? MAKING THE if. l

Application filed April 13,

This invention relates to a new process for the manufacture of footwear, especially tennis footwear, and the article thereby produced.'

It has been customary in the manufacture of tennis footwear to apply naphtha cement, commonly known as top or edging cement, to the lower inner margin of the canvas upper and to allow such cement to dry so as to 10 form a tacky surface. Similar cement is applied to the bottom of the insole and allowed to dry. The insole is placed on a last, the cemented portion of the canvas upper 1s placed against the cemented 'portion of the insole and the upper drawn down irmly over the last to remove wrinkles therefrom and cause the upper and insole to adhere together. The next step in the manufacture of tennis foot-- wear is to apply a coatof marking cement so around the lower side portion of the canvas upper and at the-same time to apply cement over the lower part of the shoe consisting of the bottom edge of the up er and the bottom of the insole. This marking cement is allowed to dry and a second or several further coats of cement may be similarly applied, if desired. A rubber upper strip, commonly known as a foxing, is then applied to the lower side portion of the upper, the marking cement serving to hold the foxing to the upr. If desired, as is usually the case in the Egttcr grades of footwear, a lling sole is cemented to the bottom of the insole. An outsole is then cemented to the bottom of a shoe, and the shoe finished in the usual manner.

This method of building canvas footwear is open to certain 'serious objections. The top and insole cements as applied contain approximately -35 per cent rubber compound and 65-70 per cent solvent. The common solvent employed today is the average grade of naphtha, havin a Baum ranging from 68 to 72. In maiing tennis footwear the uncured stren h and adhesive properties of this top and insole cement are of vital importance, in that they hold the insole and top together while the shoe is in the various stages of assembling. In lasting a canvas upper to an insole the upper is placed under considerable tension, in order to pull the fabramera p A f1 IL OLD D. RICE, OF BRISTOL, RHODE ISLN'D, ASSIGNOB TO THE GOOD INDIA RUBBER GLOVE MANUFACTURING COMPANY, OENAUGATUCK, CONNECTICUT, A COR- 1931. Serial No. 529,825.

ric over onto the insole, giving a lirmly and tightly lasted canvas upper. In fact, it is common practice today to use what is known as a bed laster, in which the'canvas upper is pulled over onto the insole with claws which are operated with considerable pressure. The marking cements in common use'consist of approximately 25 per cent rubber compound and 75 per cent solvent, which usually is naphtha similar to that used inthe top cement. When the marking cement is a plied, the solvent penetrates through the fa ric of the upper and comes into contact with the top cement which was employed to unite the insole and upper thereby frequently causing the separation of2 the insole and upper, which necessitates the re-lasting of the shoe. This re-lasting operation must be done by hand and is accordingly an expensive operation, withdanger of soiling parts, and is usually a poorly executed operation. In addition, after the toes `and heels are skived and the shoes open up, there is considerable danger of the marking cement seepin through to the inside of the shoe and soiling he inside parts. Furthermore, when the shoe opens up and is not put back in place properly the top cement is liable to show on-the inslde of the shoe, which naturally detracts from the appearance.

It is the object of this invention to provide a new process whereby the action of solvent from the marking cement upon the top cement which unites the upper and insole is prevented. It is a further object of a5 my invention to provide a new process for Abuilding tennis shoes which will produce tennis footwear in which the canvas tops present a far more uniform appearance and more closely resemble the cut of the last.

In carrying out my invention, a coat of latex or preferably of compounded latex is applied to the lower inner margin of the canvas upper. This coat of latex may be dried at normal temperatures or at elevatedl tem. peratures, such as M30-200 F., or the solid constituents vthereof may be caused to deposit by coagulation or an other convenlent and suitable manner. t is also advisable to apply a similar type of latex com- 100 pound to the insole in that it is found that the adhesion of the top to the insole is far greater if a latex composition is also applied to the insole. However, if desired, ordinary insole cement may be applied to the insole. When the latex composition on the lower inner margin of the canvasupper and the latex composition or rubber cement on the insole are dried, the upper is lasted to the insole in the usual manner. After the lasting operation, the article is ready for the marking operation. Marking cement is then applied over the lower part of the shoe consisting of the bottom edge of the upper and the bottom of the insole in the usual manner and foxing is then applied to the lower portion of the upper over the marking cement. The filling sole, if one is used, and outsole are applied to the bottom of the shoe in the usual manner. lt will be seen that when the marking cement is applied to 'the lower side portion of the u per, there is a film of the rubber deposit oi) a-lateX composition on the adjacent inner portion of the upper. The

solvent from ordinary rubber cement will not dissolve or react with a rubber iilm deposited from latex composition as it will with a film of dried rubber cement. rlherefore, when the solvent from the marking cement penetrates the lower portion of the canvas upper, it will contact on theV inner surface thereof a film of rubber deposited from latex uniting the upper and insole and hence will not dissolve or react with su'ch film and thus cause a separation of the upper and insole as VWouid ha pen in the ordinary practice or uniting t e upper and insole with naphtha cement. Ainstead of applying naph- 'tba marking cement over the lower part of the shoe consisting oi the bottom edge of the upper and the bottom or the insole in the usual manner, a layer of the solid constituents ci a latex composition may be deposited on the lower part of the shoe and if desired naplitha cement applied over such iayer, and the oxing sinned either to ther deposit of the solid constituents of the latex composition or to the. rubber cement over such deposit depending on whether the rubber cement is applied over the latex deposit, vdisclosed my copending application No. 295,357 filed July 25, 1928, now Patent No. LSOfLO, dated April l, 1931. lnstead of applying naphtha marking cement on the bottom edgeoi the upper, axing a ioxing to the shoe by means of such cement, a oxing may be 'formed in situ on the bottom edge of tlieiupper by depositing directly thereon the solid constituents of an aqueous dispersion of rubber as disclosed in copending application Se No. 295,358 Sled Juiy 25, 1928, non' Patent No. 06, dated April iii, 1931. The assem- `film 2 of dried compounded latex uniting the top 3 and insole 4, and a film 5 of dried mark- .ing cement on the lower side portion of theupper uniting the foxing 6 to the said lower portion of the upper. A filling sole is shown cemented to the insole 4 and an outsole 8 cemented to the iilling sole 7.

I prefer Ato use a latex composition for the top containing approximately 40% total solids and a latex composition for the insole with slightly less total solids,.the latices for the top and insole being thickened to the viscosity desired depending upon whether they are to be applied by hand or by machine. The compounded latex that I prefer consists of, by weight: Rubber (170 parts of latex at 58.8% solids 100 Sulphur i Rosin soap 20 Paraiin oil 2.5 28% ammonium hydroxide 3.5 Condensation product of heptaldehyde and aniline 1.00 Ammonium alginate 33 Water 102 To this composition a suiiicient amount of water may be added to give the total solid content desired for a top cement or insole cement, as described above. The latex used in the above composition is made from normal latex by creaining with an agent such as alginate or irish moss in a manner well known in the art and which creaining operation reduces the amount oi water soluble material present and greatly improves the tackiiiess of the latex. The sulphur is a curing agent and is used in conjunction with the condensation product of heptaldeliyde and aniline preferably added in the form of an emulsion,

which serves as an accelerator. rThe paraine oil which serves as a scitening agent is added in the forni of an emulsion together with the rosin soapand ammonium hydroxide. The ammonium alginate is used as a thickening agent to control the viscosity, as described a ove. Other forms of latex, such as normal latex, latex'butter, vulcanized inten, or artificial dispersione; or rubber, may be 'used iii myprocess. The term aqueous dispersion oi ru Der used in the claims is intended to cover compositions mudo roni the various kinds of atex or other water dispersions of rubber either natural or artificial. Other well known accelerators may be used instead of the one 3 rubber cement to an insole, drymg said latex composition and said cement, and uniting the upper and the insole by means of said latex composition and said cement.

2. In the vmanufacture of footwear, the ste s ofv applying an aqueous dispersion of rub er to the lower inner margin of an upper, applying an aqueous dispersion of rubber to an insole, causing the solid constituents ofl said dispersions to deposit thereon, uniting said upper and said insole by means of said deposit, a plying a foxing to the lower side portion of) to said upper and insole, andvulcanizing the rubber portions of said article.

3.' In the manufacture of footwear, the stepsof applying an aqueousdis ersion of rubber to the lower inner margin o an upper, causing the solid constituents of said dispersion to deposit thereon, applying rubbery cement to an insole, drying said cement, uniting the upper and the insole by means of said deposit and said cement, and applyingia foxing to the lower side portion of said upper.

4. A vulcanized article of footwear comprisingan upper,'an insole, a layer of the solfls deposit of an aqueous dispersion of rubber between said upper and `said insole, a foxing on the lower side portion of said upper, a layer of cement uniting said. foxin to said lower side portion of said upper, an an outsole aiiixed to said insole.

5. A vulcanized article of footwear comprising an upper, an insole, a layer of the solids deposit of an aqueous dispersion of rubber between said upper and said insole, a foxing on the lower side portion of said upper, a layer ofthe solids deposit of an aqueous dispersion of rubber between said foxing and said lower side portion of said upper, and an outsole aliixed to said insole.

v6'. A vulcanized article of footwear having an upper, an insole, a layer of the solids deposit of an aqueous dispersion of rubber between' said upper and said insole, a -forring affixed to the lower side portion of said upper, and an outsole aiiixed to said insole.

7. An article of footwear comprising an u per, an insole, a layer of the solids de osit o a latex composition and a la er of ru ber cement uniting said upper an said insole,

said upper, applying an outsole and a foxingaxed to the lower side portion of said upper.

8. Avulcanized article of footwear having an upper, an insole, a layer of the solids deposit of an aqueous dispersion of rubber be- 7 tween said upper and said insole, and an outsole afiixed to 's'aid insole.

Signed at Bristol, county of Bristol, State of Rhode Island, this 11th da' of April, 1931.

HARO D D. RICE. 

